The disclosed embodiment relates to an improved system of on-line selectable hole punching of printed sheets of paper or the like as they are being outputted by a copier or printer, which is simple, low cost, and compact, and can be integrated entirely within an existing compiler/stacker sheet output system for said reproduction apparatus. In this disclosed system, each sheet is individually hole punched, one sheet at a time, as each sheet is outputted and commonly stacked, using the preceding punch holes in the underlying sheets of the stack as a punch dye, thus allowing a much lower punching force for the hole punching as compared to hole punching through an entire set of sheets at once.
Users of copiers, printers, or other reproduction apparatus frequently desire their print jobs to be outputted as sets of printed sheets already prepunched, so that the job sets can be directly or even automatically put into three ring, two ring, or other standard notebooks or binders. Such binders typically require sheets with holes of an appropriate number and spacing from the edge margin of the sheet and from one another.
Commonly, this is now provided by loading prepunched paper stock into the copier or printer and then printing on those prepunched sheets. This has, however, several disadvantages. First, it required pre-ordering, purchasing, stocking and warehousing of such special prepunched paper, so that it is available when such print jobs are needed. Several different weights, sizes, and/or colors of such special use prepunched paper may be required to be stored on hand, with associated inventory and other costs. Secondly, prepunched holes in the sheets can interfere with proper feeding or printing of such sheets; for example, by falsely actuating or triggering lead or trail edge sheet sensors in the sheet feeding path of the printer or copier. Thirdly, since the first or odd page of the print job must have the prepunched holes on the left margin of the sheet, not the right margin, and so forth for subsequent pages, the orientation in which such prepunched sheets are loaded into the copier or printer is critical for proper orientation of the printed image relative to the holes. Such prepunched stock is, of course, not even available for roll or web fed copiers or printers as opposed to pre-cut sheet fed copiers or printers. Nor is it suitable for letterhead or other pre-printed paper stock.
To overcome the above and other disadvantages of prepunched (also referred to as predrilled) paper stock, some copiers have begun to offer on-line hole punching of the sheets during or immediately after the printing process in the copier, so that conventional unpunched blank copy sheet stock may be utilized, yet provide appropriately punched print jobs in the output. Also, it has been suggested in prior patents. Noted, for example, is Xerox Corporation U.S. Pat. No. 4,819,021 issued Apr. 4, 1989 is to Michael S. Doery, noting particularly the left-hand sides of FIGS. 3 and 4 and Col. 8 (Attorney Docket No. D/86170). IBM Technical Disclosure Bulletin Vol. 22, No. 8A, January 1980, pages 3119-3120, discloses a multiple pattern rotary punch of a type previously used for punching rolls of web-like material, for use in in-line copier or offset press oscillatory punching of single copy sheets. The punch device disclosed can be fitted with different arrays of hole patterns. Mead Corporation U.S. Pat. No. 4,575,296 issued Mar. 11, 1986 to Kockler, et al, especially the bottom of Col. 3, and reference No. 40, also suggests on-line hole punching. Also, Canon U.S. Pat. No. 4,763,167 issued Aug. 9, 1988 to T. Watanabe, et al; and Mita U.S. Pat. No. 5,508,799 issued Apr. 16, 1996 to Irie. On-line hole punching of the copier output is believed to have been available in a Konica xe2x80x9c7090 RFxe2x80x9d product since approximately 1988. Noted is Konica U.S. Pat. No. 4,988,030 issued Jan. 29, 1991 to Muramatu et al. Further, Xerox Corporation U.S. Pat. No. 5,628,502 issued May 13, 1997 to Kiri Amarakoon, discloses a sheet output system with a stacking tray for accumulating, registering, and stacking on top of preceding sheets in a superposed set stack the printed sheets sequentially individually outputted by a reproduction system; a low force sheet hole punching system integral the output stacking tray for punching holes through only one individual sheet at a time on top of the set stack, before the next sequential sheet is so registered and stacked, with all of the sheets having underlying commonly superposed sheet holes which function as a punch die.
These references also note that on-line hole punching can be provided with or without stapling or other set binding in addition thereto, a feature for which the disclosed embodiments are also compatible.
The disclosed system is usable with a wide variety of sheet output compilers and stackers. Some examples include Xerox Corp. U.S. Pat. Nos. 4,541,626; 4,826,383; 5,044,625; 5,201,517; 5,120,047; 5,014,977; 5,289,251; 5,342,034; 5,261,655; and 5,409,202; and other references cited therein. As will be further described herein, the disclosed embodiment integrally incorporates an on-line hole punching system into a compiler/stacker in a manner which is fully compatible with and may cooperatively utilize the sheet entrainment and movement provided by the compiler/stacker, and other elements thereof. This integrated system enables optional on-line hole punching to be provided in the output sheets without any increase in the overall size of the sheet output system, or any reduction in printing speed. Also, the sheet punching as disclosed herein is desirably at the exposed output end of the printing system, and therefore is readily accessible for adjustments, repairs, and, most importantly, jam clearances of any sheet jams or removal of sheets during machine stoppages. That is, the hole punching system disclosed herein is not buried internally within the copier or printer in an access-restricted location.
Another advantage of the disclosed integral hole punching and stacking embodiment is that the hole punching is accomplished on-line yet without having to interrupt, even briefly, the sheets printing. Yet, the sheet edge is registered and deskewed before and during hole punching here, which is essential for proper positioning of the punched holes in the sheets and for consistent hole positions in the outputted set. Not only is the edge of the sheet being punched here registered, the existing transverse registration system of the existing compiler/stacker, of, for example, said above-cited patents, may desirably be utilized to provide transverse registration of the sheet prior to its hole punching as well. That is, both of the existing process direction and lateral registration systems provided by the output stacker can provide a dual mode function, in that they can also provide both forward and lateral registration of the sheet for punching of the desired pattern of holes therein in the proper positions therein. Thus, preexisting registration and stacking systems can be used with only minor, low cost, additions or modifications.
As noted, a particular advantage of the disclosed system is that the hole punching force is greatly reduced. Here, only one sheet at a time is punched, rather than a whole set of sheets.
A specific feature of the specific embodiments disclosed herein is to provide, in a sheet output registering and stacking system with an output stacking tray for accumulating, registering, and stacking on top of preceding sheets in a superposed set stack the printed sheets sequentially individually outputted by a reproduction system, the improvement comprising a low force on-line sheet hole punching system integral said output stacking tray for punching holes through only one said individual sheet at a time on top of said superposed set stack of printed sheets as each said individual sheet is so registered and stacked, and before the next sequential sheet is so registered and stacked, so that all of the preceding sheets of said set stack have underlying commonly superposed holes.
Further specific features disclosed herein, individually or in combination, include those wherein said low force sheet hole punching system has a hole punch normally overlying said superposed set stack of printed sheets in said stacking tray and reciprocally drivable through said individual sheet on top of said superposed set stack of printed sheets and at least partially through said underlying commonly superposed holes of said underlying sheets of said set stack, which superposed holes of said underlying sheets function as a punch die; and wherein said hole punch has a reciprocal punch driving system automatically actuated as each said individual sheet is so registered and stacked, and before the next sequential sheet is so registered and stacked; and/or wherein there is additionally provided a mating punch die provided by an aperture in said stacking tray underlying said superposed set stack of printed sheets and said hole punch for functioning as a punch die for the initial sheets of said set stack; and/or wherein a punch waste paper container is mounted under said aperture in stacking tray; and/or wherein a sheet set clamp is mounted with said hole punch to be driven down with said hole punch by said reciprocal punch driving system until said set clamp forcibly engages said individual sheet against said superposed set stack of printed sheets.
The disclosed system may be operated and controlled by appropriate operation of conventional control systems. It is well known and preferable to program and execute imaging, printing, paper handling, and other control functions and logic with software instructions for conventional or general purpose microprocessors, as taught by numerous prior patents and commercial products. Such programming or software may of course vary depending on the particular functions, software type, and microprocessor or other computer system utilized, but will be available to, or readily programmable without undue experimentation from, functional descriptions, such as those provided herein, and/or prior knowledge of functions which are conventional, together with general knowledge in the software and computer arts. Alternatively, the disclosed control system or method may be implemented partially or fully in hardware, using standard logic circuits or single chip VLSI designs. Conventional sheet path sensors or switches connected to the controller may be utilized for sensing, counting, and timing the positions of sheets in the sheet paths, and thereby also controlling the operation of sheet feeders and inverters, as well as the hole punch driver, etc., as is well known in the art.
As to specific components of the subject apparatus, or alternatives therefor, it will be appreciated that, as is normally the case, some such components are known per se in other apparatus or applications which may be additionally or alternatively used herein, including those from art cited herein. All references cited in this specification, and their references, are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features, and/or technical background. What is well known to those skilled in the art need not be described here.